Calcium Carbonate → Ethyl 2-(pyridin-4-yl)-6,7-dihydrothiazolo[5,4-c]pyridine-5(4H)-carboxylate

HRID 2388718Notes

Reaction equation

HRID 2388718 reaction equation
[C:1]([NH2:9])(=[S:8])[C:2]1[CH:7]=[CH:6][N:5]=[CH:4][CH:3]=1.C(=O)([O-])[O-].[Ca+2].Br[CH:16]1[C:21](=O)[CH2:20][CH2:19][N:18]([C:23]([O:25][CH2:26][CH3:27])=[O:24])[CH2:17]1>CC(O)C>[N:5]1[CH:6]=[CH:7][C:2]([C:1]2[S:8][C:16]3[CH2:17][N:18]([C:23]([O:25][CH2:26][CH3:27])=[O:24])[CH2:19][CH2:20][C:21]=3[N:9]=2)=[CH:3][CH:4]=1

Participants

5

Reactant 3

HCID 10112Calcium CarbonateHCID 27237884-PyridinecarbothioamideHCID 13799628Ethyl 3-bromo-4-oxopiperidine-1-carboxylate

Product 1

HCID 68644063Ethyl 2-(pyridin-4-yl)-6,7-dihydrothiazolo[5,4-c]pyridine-5(4H)-carboxylateYield 20%

Reagents, catalysts & solvents 1

HCID 3776IsopropanolSolvent

Conditions

Temperature
25 °C

Procedure

Thioisonicotinamide (18 mmol) and calcium carbonate (200 mmol) were added to a solution of ethyl 3-bromo-4-oxopiperidine-1-carboxylate (5 g; 20 mmol) in 2-propanol (60 ml). The reaction mixture obtained was heated under reflux for 48 hours. The course of the reaction was monitored by thin layer chromatography. The reaction mixture was then cooled to 25° C. and filtered over Celite and the filter cake was washed several times with ethyl acetate. The organic phase was concentrated under reduced pressure, the residue was taken up in ethyl acetate and the mixture was washed successively with water and saturated sodium chloride solution. After the organic phase had been dried over sodium sulfate, the solvent was removed under reduced pressure. The crude product obtained was purified by column chromatography (30% ethyl acetate in hexane). The desired product was obtained in a yield of 20%.

Workup

  1. customThe reaction mixture obtained
  2. temperaturewas heated
  3. temperatureunder reflux for 48 hours
  4. filtrationfiltered over Celite
  5. washthe filter cake was washed several times with ethyl acetate
  6. concentrationThe organic phase was concentrated under reduced pressure
  7. washthe mixture was washed successively with water and saturated sodium chloride solution
  8. dry with materialAfter the organic phase had been dried over sodium sulfate
  9. customthe solvent was removed under reduced pressure
  10. customThe crude product obtained
  11. customwas purified by column chromatography (30% ethyl acetate in hexane)

Sources & evidence

ORD record
ord-e281ea5b4bee4b11a23f825b45084001
Source dataset
uspto-grants-2012_09
Patent number
US08268814B2

Reaction notes

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